Two ways a cached entry could be wrong.
The key was built by string concatenation in parallel with the URL, so
`search_movies("dune&year=2024", None)` and `search_movies("dune",
Some(2024))` produced the same key for two different requests. Both key
and URL now come from one `Url`, percent-encoded identically, and the
API key is appended at send time so it cannot reach a key or a log.
A successful response was cached before it was decoded, so one malformed
body returned `Error::Decode` from the cache for the whole time-to-live.
Decoding now happens first and only what decoded is stored.
Miguel Palhas
502a431de3